1. Field of the Invention
This application is directed to amine coupled hindered phenol and phosphite derivatives useful as multifunctional antioxidant/antiwear lubricant additives and to lubricant compositions comprised thereof.
2. Description of Related Art
The use of hindered phenols, such as 2,6-di-tert-butylphenol and 2,6-di-tert-butyl-para-cresol, has been well known for their thermal/oxidation stabilizing properties in a variety of lubricant, polymer and elastomer applications.
The use of amine derivatives, such as amine phosphate salts, has been widespread for several decades as corrosion inhibitors and antiwear/EP additives.
The use of phosphite (hydrogen phosphonate) compositions, such as dibutyl phosphite and dinonylphenyl phosphite, has also been well known in lubricants as antiwear/EP additives.
It has now been found that the use of these amine coupled condensation products of hindered phenols and phosphites provides exceptional antioxidant and antiwear/EP activity with potential thermal stabilizing and metal chelating properties.